BONDTECH Extruder Filament Guide

When I updated my BONDTECH BMG extruder to a DIRECT DRIVE setup, I found that I needed to develop a way to deliver the filament into the top of the extruder. I finally decided to use about 1 1/2 feet of thin wall (4MM OD, 3MM ID) poly tube similar to a BOWDEN setup. I mounted the input side of the filament feed-tube to the printer frame just above the spool holder, and then slipped the feed tube into the top of the BMG extruder using it's normal 4mm bowden tube coupler. While this got me started, I soon found two small issues.

1. Since the ID of the thin-wall tubing is large (3 mm), the 1.75mm diameter filament easily slips through the tubing and on into the DIRECT DRIVE extruder. This is good! However, unlike its thick-wall Bowden tube counterpart, the thin-wall tubing (4mm OD, 3MM ID) is less rigid and therefore more prone to kinks and bends near the top of the BMG input port fitting as the carriage moves about. These kinks can pinch the filament and cause findup which can i